Automatic time-stop.



L. v. MADDOX. AUTOMATIC TIME STOP.

APPLICATION TILED MAR. 31, 1913. 1 107,332 Patented Aug. 18, 1914.

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AUTOMATIC TIME STOP APPLICATION FILED MAR. 31, 1913 1 107,332. Patented Aug. 18, 1914.

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1 m. 36? W a J [/1 Vl/ 4 wowmto'c UNITED STATES PATENT OFFICE.

LOFTON V. MADDOX, 0F COLDWATER, TENNESSEE.

AUTOMATIC TIME-STOP.

To all whom it may concern:

Be it known that I, LOFTON V. MADnox, a citizen of the United States, residing at Goldwater, in the county of Lincoln and State of Tennessee, have invented certain new and useful Improvements in Automatic Another object of this invention is the provision of an automatic time stop comprising a frame having a plurality of inter meshing gear wheels rotatably supported therein, the gear wheels being operat-ively connected to the governorshaft oftheengine, one of the gear wheels having a pointer s'e cured thereto, the pointer being adapted to release a spring operated slide or rack bar after a predetermined number of revolutions or oscillations of the governor shaft, the slide bar being operatively connected to the gasolene cut off screw to rotate the same and close the gasolene valve, thereby'stopping the engine.

A still further object of this invention is the provision of a time stop 'mechanism comprising a springl operated slide bar which is adapted to be released after a predetermined number of revolutions of the governor shaft of the engine, the rack bar being adapted to rotate the gasolene cut off screw, and the rack bar being also'adapted to release the connection of the battery wires which furnish the spark in the cylinders of the engine.

lVith these and other objects in view, my invention consists in certain novel constructions, combinations and arrangements of arts to be hereinafter more fully described, claimed and illustrated in the accompanying drawings, in Which Figure 1 is a front view of my device showing it attached to an engine; Fig. '2

is a front view thereof detached from the engine; Fig. 3 isa vertical section thereof; Fig- L is a horizontal section through the top of the casing; Fig-5 is a top plan view; and

Fig. 6 is a fragmentary elevation of an alternative form of my invention,

Specification of Letters Patent.

1 Application filed March 31, 1913.

Patented Aug. 18, 1914.

Serial No. 757,943.

Referring more particularly to the drawings, the letter A designates an engine of any desired construction, the engine having a rotatable governor shaft 5 and a gasolene cut off screw 6, the head of which is formed with a series of teeth 7 The letterB designates generally my improved time stop mechanism which comprises a rectangular frame 8 consisting of spaced walls in which are mounted two vertically spaced rotary horizontal shafts 9 and 10, the upper shaft 9 having a gear wheel 11 secured thereto intermediate of its ends, and the lower shaft 10 having a similar gear wheel 12-secured thereon at one end. A vertically disposed rotatable shaft 13 is also mounted in the frame, the shaft having a gear wheel 14 secured thereto near its lower end, the gear wheel being adapted to mesh with the worm screw 15 on the lower shaft 10, the shaft 13 being also provided with a worm screw 16 which is adapted to mesh with the gear wheel 11 on the upper shaft 9. The shaft 9 projects through one wall of the frame, and a dial 17 is arranged on the outerface of the wall surrounding the shaft 9, the extremity of the shaft having a pointer or hand 18 adjustably secured thereon by a set screw 19; A horizontally extending bar 20 is slidably disposed in openings 21 in the frame, the bar being provided at one end with a series of teeth 22 which are adapted to mesh with the teeth 7 on the head of the gasolene cut off screw 6. The opposite end of the slide bar is provided with a series of openings 23, and pivotally mounted upon the outer face of one side wall of the frame is a bell crank lever 24, one arm 25 thereof being disposed in the path of the hand 18, the other arm 26 being ofiset at its extremity to form a hook or catch 27 for engagement in one of the openings 23 in the slide bar. A coil expansion spring 28 is arranged about the bar intermediate of its ends, one end of the spring bearing against the inner face of the outer wall of the frame, and the opposite end of the spring bearing against a pin 29* 1 the hand 18 can be set at the upper face of the top wall, and having a hand 33 composed of nonconductive material secured thereto.

Secured in the upper face of the top wail of the frame are a pair of contacts 84: and 34c to which wires 35 of a battery 85 are secured, the wires being maintained in circuit with each other by an arm 35 which is loosely secured to the contact 34 and is adaptedto engage the other contact 34.

I Pivotally secured to the under face of the top wall of the frame is a trigger 36, one end thereof being disposed in the path of the pin 29 in the slide bar, and the opposite end thereof being offset, as at 37, to engage the cogs of one of the gear wheels 30 of the spring motor.

Assuming that the engine to which my improved time stop mechanism is connected with, is one of the four-cycle type the fly wheel of which revolves 600 times per minute, it will be evident that in twelve hours the 'fly wheel will make 432,000 revolutions. As the governor shaft in the four-cycle engine is rotated only half the number of times of the revolutions of the fly wheel, the governor shaft in this instance will make 216,000 revolutions in twelve hours. The governor shaft 5 is operatively connected to the time stop mechanism by the engagement of a worm screw 38 which meshes with the gear wheel 12 whereby the time stop mechanism will be operated upon rotation of the governor shaft.

The gear wheels 11, 12 and 14 in the frame are provided with a suitable number of teeth so that the shaft 9 upon which the hand or pointer 18 is mounted will make but one complete revolution during the twelve hours that the engine is running. The dial is provided with three annular series of graduations, so that the improved stop mechanism can be operatively con nected to engines'of different speeds, and any hour marked on the dial so that the engine will runa predetermined length of time before the hand strikes the arm of the bell crank lever 24. When the hand strikes the bell crank lever, the hooked end 27 of the arm 26 is disengaged from the opening 23 in the slide bar, and'by reason of the spring 28, the bar is moved toward the cut off screw which is rotated by the intermeshing teeth 22 and 7 on the bar and screw respectively. As the bar is moved toward the cut off screw 6, the pin 29 engages the end 36 of the trigger, which moves the offset end 37 thereof out of engagement with the gear wheel of the spring motor, thereby allowing the gear wheels to rotate, whereby the hand 33 is rotated to disengage the arm from the contact 34 thereby cuttingout the circuit of the battery wires and stopping the spark in the cylinders of the engine. By reason of the spring motor, the connection of the battery wires is not broken until a predetermined time after the gasolene has been cut off from the carbureter, so that the gasolene which remains in the cylinders after the supply has been cut off will be utilized to drive the engine.

In Fig. 6 of the drawings I have illus trated an alternative means of operating the time stop mechanism, when it is used inconnection with an engine having a reciprocating governor rod. In this form, the governor rod 39 is provided with a pair of spaced pins 10 between which are slidably mounted one end of an arm 41 which is pivotally mounted on one wall of the frame 8. Pivotally mounted on the arm intermedi ate of its ends is a pawl 42 which is adapted to engage the teeth on the gear wheel 12 to rotate the same upon movement of the governor rod in one direction: Pivotally mounted on the frame is a pawl 43 which is also adapted to engage the teeth on the gear wheel 12 to prevent reverse rotation of the gear wheel upon movement of the governor rod in the opposite direction.

It will be understood that if a magneto is used in connection with the engine, the

spring motor to disconnect the sparking mechanism from the engine Wlll not be necessary.

From the above description taken in connection with the accompanying drawings, it will be seen that 1 have provided an automatic time stop mechanism for engines which may be operatively connected to an engine of any construction and one which makes any number of revolutions in a giventime, and it will be evident from the drawing that the mechanism comprises a relatively small number of parts, whereby it may be cheaply manufactured. Of course the engine may be allowed to run any desired length of time, it being merely necessary to change the number of teeth on the gear wheels 11, 12 and 14, or to provide a greater or less number of wheels through which the motion of the governor shaft is transmitted to the hand 18.

Having thus fully described my invention what I desire to claim and secure by Letters Patent is:

1. The combination with an engine having a governor shaft and a fuel cut off screw, of stopping mechanism comprising a frame having a plurality of intermeshing gear wheels rotatably mounted therein, one of said gear wheels .being operatively connected to said governor shaft, a bar slidably mounted in said frame and operatively connected with said out oif screw, a lever pivotally mounted on said frame and engaging said slide bar, and means connected with another of said gear wheels to release said lever from engagement with said slide bar upon predetermined rotation ofthe last mentioned gear wheel, as and for the purpose described. r

2. The combination with an engine hav ing a governor shaft and a fuel cut off screw, of stopping mechanism comprising a frame having a plurality of intermesh'rfig gear wheels rotatably mounted therein, one of said gear wheels being operatively connected to said governor shaft, a bar slidably mounted in said frame, one end of said bar being operatively connected to said out off screw, a hand secured to another of said rotatable wheels, a bell crank lever pivotally mounted upon said frame, one arm of said bell crank lever being engaged with said slide bar to prevent movement thereof, and

the other arm of said bell crank lever being disposed in the ,path of movement of said hand, whereby said lever will be released from engagement with said bar upon predetermined rotation of the last mentioned gear Wheel, as and for the purpose described.

3. The combination with an engine having a governor shaft and a spark producing battery, of stopping mechanism comprising a frame having a plurality of intermeshing gear wheels rotatably mounted therein, one of said gear wheels being operatively connected to said governor shaft, a bar slidably mounted in said frame, means for holding said slide bar stationary with relation to said frame, means operatively connected to another of said gear wheels for releasing said means for holding said slide bar, said slide bar being adapted to cut offthe supply of fuel to the engine, and means operatively connected to said slide bar to break the circuit of said battery, as-and for the purpose described.

4. The combinationwith an engine having a governor shaft, and a fuel cut-ofi' screw, of a stopping mechanism comprising a plurality of intermeshing gear wheels, one of said gear wheels being operatively con-' nected to said governor shaft, a rack-bar operatively connected with said cut-ofi' screw, means for normally holding said rack-bar stationary, means co-acting with one of said wheels for releasing said bar from the first said means, and means for moving the rack-bar immediately after being released.

In testimon whereof I hereunto affix my signature in the presence of two witnesses.

LOFTON V. ,MADDOX.

Witnesses: I

D. O. SHEBRELL, J. BOONE Larmrss. 

